In recent years,rapid urbanization has had a profound impact on landscape stability.As a typical example of China's rapid urbanization,Hangzhou has also experienced significant landscape changes,which have profoun...In recent years,rapid urbanization has had a profound impact on landscape stability.As a typical example of China's rapid urbanization,Hangzhou has also experienced significant landscape changes,which have profoundly affected its ecological stability.Taking Hangzhou as an example,this study integrates land use change data from 1980 to 2020,combines dynamic simulation and ecological modeling techniques,and carries out a comprehensive analysis of historical trends and future predictions,to provide valuable insights into the complex interactions between urban expansion and landscape stability.The results indicate that:1)between 1980 and2020,Hangzhou experienced a significant increase in construction land at the expense of arable land,leading to a gradual decline in landscape stability,though the downward trend has slowed in recent years.2)The spatial distribution of landscape stability shows clear aggregation patterns,with lower stability concentrated in economically active flatlands and higher stability in the mountainous western regions.3)By 2040,further urban expansion is predicted to occur alongside increased landscape integration,reflecting the positive effects of ecological protection strategies.This study highlights the universal challenges of balancing economic growth with ecological stability in rapidly urbanizing regions.The combination of advanced simulation models and spatiotemporal analysis demonstrates a replicable framework for assessing urban expansion's ecological impacts.These findings underscore the importance of tailoring urban planning and ecological policies to address regional disparities,providing valuable insights for sustainable urban development and landscape management globally.展开更多
The relationship between landslides,land use,and sediment connectivity is not only a critical interdisciplinary topic,but also remains a challenging issue in assessing dynamic landslide susceptibility within reservoir...The relationship between landslides,land use,and sediment connectivity is not only a critical interdisciplinary topic,but also remains a challenging issue in assessing dynamic landslide susceptibility within reservoir areas.To explore the interactions among landslide,land use changes,and sediment dynamic,this study took Zigui Basin,the head area of the Three Gorges Reservoir,as the study area to examine this triadic relationship by single-factor detection and interactive detection.Here,we utilized Dynamic Attitude(DA)analysis to quantify land use changes and applied the Index of Connectivity(IC)to assess sediment connectivity evolution from 2018 to 2023.A multi-temporal analysis using the Landslide Susceptibility Index(LSI)was conducted to evaluate the degree of transformation in the three objects and the influence of these changes on the landslide susceptibility.According to the spatial analyst and statistics tools in ArcGIS,the results reveal that most of the landslides distributed in areas with high land use dynamic attitude,such as cultivated land transfers to forestland or garden plot,and the garden plot continuously increased across the study period with largest variation of 5%and an increment of 1.9%.Furthermore,linkage between land use and sediment transport can be effectively quantified by IC,and the resulting map indicated that garden plot increased,and catchment channel characteristics had a greater influence on the IC value than differences in vegetation cover.A comprehensive evaluation of the differences among the susceptibility maps reveals that the very high susceptibility classes are predominantly influenced by enhanced connectivity,whereas land use change has a greater effect on medium-low susceptibility region than that of sediment evolution.That is,both changes of land use and connectivity have positively correlated with landslide activity,but they exhibit differential influences on landslides susceptibility.展开更多
Mountainous minority regions in China,characterized by abundant natural and cultural resources,ecologically fragile environments,and often geographically remote locations,pose distinct developmental challenges and opp...Mountainous minority regions in China,characterized by abundant natural and cultural resources,ecologically fragile environments,and often geographically remote locations,pose distinct developmental challenges and opportunities.Despite the complexity and typicality of Chinese mountainous ethnic minority regions in terms of eco-cultural tourism and land use dynamics,the interplay among tourism development,land use changes,and landscape ecological risk in these specific contexts has received insufficient attention.To explore how eco-cultural tourism development in ethnic minority mountainous regions affects land use and landscape ecology,this study investigates the evolution of land use in Southeast Guizhou Province from 1980-2020,integrating GIS spatial analysis,the landscape pattern index and landscape ecological risk index analysis.Over the past four decades(1980-2020),eco-cultural tourism has driven significant land use transformations characterized by substantial expansion of building land,growth of ecological land(notably forest land and water areas),and reduction of cultivated land.Concurrently,landscape ecological risk evolved through distinct phases-showing an overall increase during 1980-2000 with expanding medium-risk zones,followed by stabilization from 2000-2020.Tourism development accelerated these land transitions while fostering multifunctional compound land uses,enhancing both land value and utilization efficiency.Crucially,eco-cultural tourism in ethnic regions demonstrates capacity to reconcile ecological conservation with economic development,providing transferable models for similar regions globally.展开更多
As one of the important wintering areas along the East Asian-Australasian Flyway,wetlands in the Yangtze River floodplain face threats from land-use changes,yet its effects on wintering waterbirds at the landscape lev...As one of the important wintering areas along the East Asian-Australasian Flyway,wetlands in the Yangtze River floodplain face threats from land-use changes,yet its effects on wintering waterbirds at the landscape level remain understudied,impeding conservation practice.Here,using survey data collected across 14 inland lakes in Jiangsu Province in 2022,we calculated wintering waterbirds diversity(taxonomic,functional,phylogenetic)and assembly patterns(MPD/MNTD of functional and phylogenetic).Then,we interpreted satellite imagery of lake areas and buffer zones(5 km),and partitioned them into three land-use and landscape index categories(anthropogenic,ecological,and lake landscape).Finally,we employed multiple linear regression and hierarchical partitioning to explain the influence of landscape scales on wintering waterbird communities.Our results showed that the diversity and assembly of regional wintering waterbird communities tended to be consistent across taxonomic,functional,and phylogenetic dimensions.The standardized diversity indices indicated that functional assembly of communities tends to be clustered at both local and regional scale.In contrast,the phylogenetic structure showed a predominantly overdispersed pattern in most lakes at the local scale,while neutral processes dominated at the regional scale.Modeling showed that selected variables explained waterbird diversity and assembly well.Lake fragmentation increased species evenness but reduced other diversity indices,while landscape evenness was negatively associated with functional and phylogenetic assembly.Among anthropogenic factors,aquaculture ponds and impervious surfaces reduced all diversity dimensions,whereas cropland connectivity enhanced phylogenetic diversity.These factors had consistent effects on community assembly.For ecological variables,grassland area enhanced functional and phylogenetic diversity but led to more clustered functional assembly.Overall,maintaining the integrity and connectivity of lakes and their surrounding landscapes is essential for sustaining waterbird diversity and guiding wetland restoration.展开更多
The Leymus chinensis grassland is one of themost widely distributed associations in the warmtemperate grassland and due to overgrazing in recent years,it has experienced varying degrees of degradation.Vegetative regen...The Leymus chinensis grassland is one of themost widely distributed associations in the warmtemperate grassland and due to overgrazing in recent years,it has experienced varying degrees of degradation.Vegetative regeneration via bud banks serves as the primaryway of vegetation reproduction in the L.chinensis grassland ecosystem.However,the role of the bud bank in the vegetation regeneration of grazing grassland remains unclear.Based on the relationship between the under-ground bud bank and above-ground vegetation of L.chinensis grassland under different grazing stages,this study aimed to explore whether the grazing grassland could self-recover through the existing bud bank.The findings revealed that the bud density initially increased and then decreased with increasing grazing intensity,indicating that appropriate grazing promoted vegetation renewal.Moreover,grazing significantly influenced the composition of the bud bank:during the early grazing stage,the rhizome buds accounted for the main part,and tiller buds dominated during the mid-stage grazing;while during the late-stage grazing,root-sprouting buds prevailed.The meristem restriction index for light,moderate,and heavy grazing grasslands was close to one;conversely,overgrazing and extreme overgrazing grasslands exhibited the highermeristemrestriction index(2.00,3.19),suggesting that plant regeneration was constrained by bud banks under light-grazing conditions where regenerate rates failed to meet above-ground modular’s recovery requirements following overgrazing and extreme overgrazing events.Consequently,moderate grazing grasslands could achieve natural community recovery by continuously adjusting their vegetative regeneration strategies.Understanding the role of bud banks in vegetative regeneration in grazing grassland will not only supply theoretical support for the ecological succession process of degraded grassland but also provide practical experience for the sustainable management of the L.chinensis grassland ecosystem.展开更多
The process of agricultural intensification has led to significant reductions in biodiversity globally.Previous studies examined the role of semi-natural habitats within agroecosystems in supporting bird communities,b...The process of agricultural intensification has led to significant reductions in biodiversity globally.Previous studies examined the role of semi-natural habitats within agroecosystems in supporting bird communities,but few have considered the effects of landscape agricultural intensity on avian conservation potential of seminatural habitats.Here,we disentangle the relative effects of semi-natural habitats within different landscape agricultural intensities on bird community composition in central and eastern Jilin Province,China.We established 322 sampling sites distributed across low,middle,and high landscape agricultural intensities,with 103,118,and 101 sites respectively.Each sampling site was visited two times in May and June 2023 to test the dissimilarities in bird composition between different landscape agricultural intensities.We found that middleintensity agriculture supported the highest bird diversity in most cases,but low-intensity plays an important role in maintaining insectivorous birds.We used generalized linear models and model selection to assess the relative impacts of semi-natural habitats on bird community along agricultural intensity respectively.Our results showed that the effects of agriculture on bird communities were predominantly influenced by the amount of semi-natural habitats,with effects that differ in accordance with the level of landscape agricultural intensity.Priority should be given to preserve or/and plant these semi-natural habitats in middle-intensity agriculture due to the stronger effect sizes on bird diversity.Specifically,we suggested preserving and promoting woodlands and shrubs in high-intensity agriculture,and simultaneously increasing crop diversity to protect bird diversity in agriculture landscapes in the context of increasing crop intensification globally.展开更多
Agricultural management practices influence soil health.In this study,agricultural lands of cold arid Hanna village,Balochistan,Pakistan,were studied to assess soil properties and the abundance of soil macrofauna spec...Agricultural management practices influence soil health.In this study,agricultural lands of cold arid Hanna village,Balochistan,Pakistan,were studied to assess soil properties and the abundance of soil macrofauna species.Five orchards,five tree-based intercropping(TBI)systems,two croplands and a barren unprotected rangeland were sampled.Soil properties,such as texture,concentrations of organic matter(SOM),organic carbon(SOC),mineral nitrogen and bioavailable phosphorus,pH and electrical conductivity were analyzed.The abundance and species of soil surface-dwelling and upper soil layer-dwelling(0-5 cm)macrofauna were also measured.Orchards and croplands were older than TBI systems.than the same agricultural systems(cropland or orchards),which were under intense tillage practice or receiving no fertilizer input.Our results demonstrate that the diversified cropping systems with the reduced(shallow)tillage and the amendment of both synthetic and organic fertilizers,promoted soil quality in this cold-winter desert.This study is a source of evidence for the farmers of this region,which highlights the importance of conservation agriculture and crop diversification under TBI system for improving soil quality.It warrants further investigation to evaluate biological indicators of soil health(soil microbial biomass,microbial diversity,microfauna,mesofauna and macrofauna)being influenced by various management practices in this region.Furthermore,the relationship between soil quality and crop production under various management practices in this region needs to be evaluated.Such an extensive study will further help encourage farmers to adopt the best management practice in their fields.展开更多
Improving crop productivity and soil fertility through the balanced application of inorganic and organic nutrient sources is a sustainable approach in modern agriculture.Char land soils,widely distributed in riverine ...Improving crop productivity and soil fertility through the balanced application of inorganic and organic nutrient sources is a sustainable approach in modern agriculture.Char land soils,widely distributed in riverine Bangladesh,are generally low in organic matter status and deficient in necessary nutrient elements for crop production.Addressing this challenge,the present study was conducted to investigate the effects of various organic nutrient sources with inorganic fertilizers on crop yields,nutrient uptake,and soil fertility in farm(L1)and char land(L2)of Brahmaputra River in Mymensingh,Bangladesh from 2022(Y1)to 2023(Y2).For each location,eight treatments viz.T1(Control),T2[100%recommended fertilizer dose(RFD)],T3(75%RFD),T4(75%N from RFD 25%N from cow dung),T5(75%+N from RFD 25%N from poultry manure),T6(75%N from RFD 25%N from vermicompost),T7(75%N from++RFD 25%N from household compost)and T8(75%N from RFD 25%N from rice straw compost)were arranged in++a randomized complete block design with three replications using Wheat–Mungbean–T.Aman rice cropping pattern where three way interaction was considered for results.Treatment T5 performed the best in both years in both locations as it enhanced the yield components(p 0.05)and caused yield increment over control.The yield improvement in<Char land soils was higher than that in farm soils.For all three crops,treatment T5 consistently augmented the uptake of nitrogen,phosphorus,potassium,and sulphur by different parts of the crops and improved soil fertility properties such as organic matter status,cation exchange capacity,total nitrogen,available phosphorus,and sulphur as well as exchangeable potassium in both locations in both years.Cost and return analysis of different treatments for the whole cropping system showed that the highest marginal benefit-cost ratio(16.35 and 15.07)and gross return(about Tk 768,595/ha and 728,341/ha)were obtained from the T5 treatment in farm soils and Char land soils,respectively.Followed by poultry manure,vermicompost performed well in addition to mineral fertilizers for improving crop yield and soil fertility but its economic efficiency was less due to high input cost.These findings may be useful to the smallholder farmers in char areas,who could benefit from increased productivity,reduced reliance on chemical fertilizers,and improved soil health,contributing to the long-term sustainability of char land agriculture.展开更多
Rainfall-induced landslides,exacerbated by climate change,require urgent attention to identify vulnerable regions and propose effective risk mitigation measures.Extensive research underscores the significant impact of...Rainfall-induced landslides,exacerbated by climate change,require urgent attention to identify vulnerable regions and propose effective risk mitigation measures.Extensive research underscores the significant impact of vegetation on soil properties and slope stability,emphasizing the necessity to incorporate vegetation effects into regional landslide susceptibility mapping.This review thoroughly examines research integrating vegetation into landslide susceptibility mapping,encompassing qualitative,semi-quantitative,and quantitative forecasting methods.It highlights the importance of incorporating vegetation aspects into these methods for comprehensive and accurate landslide susceptibility assessment.This review explores the diverse roles of vegetation in slope stability,covering both aggregated impacts and individual influences,including mechanical and hydrological effects on soil properties,as well as the implications of evapotranspiration and rainwater interception on slope stability.While aggregated roles are integrated into non-deterministic methods as input layers,individual roles are considered in deterministic methods.In the application of deterministic methods,it is noteworthy that a considerable number of studies primarily concentrate on the mechanical impact,particularly the reinforcement provided by root cohesion.The review also explores limitations and highlights future research prospects.In the context of mapping landslide susceptibility amid changing climatic conditions,data-driven techniques encounter challenges,while deterministic methods present their advantages.Stressing the significance of hydrological impacts,the paper recommends incorporating vegetation influences on unsaturated soil properties,including the soil water characteristic curve and soil permeability,along with pre-wetting suction due to evapotranspiration and potential rainwater interception.展开更多
This study evaluates the long-term radiometric performance of the USGS new released Landsat Collection 1 archive, including the absolute calibration of each Landsat sensor as well as the relative cross-calibration amo...This study evaluates the long-term radiometric performance of the USGS new released Landsat Collection 1 archive, including the absolute calibration of each Landsat sensor as well as the relative cross-calibration among the four most popular Landsat sensors. A total of 920 Landsat Collection 1 scenes were evaluated against the corresponding Pre-Collection images over a Pseudo-Invariant Site, Railroad Valley Playa Nevada, United States (RVPN). The radiometric performance of the six Landsat solar reflective bands, in terms of both Digital Numbers (DNs) and at-sensor Top of Atmosphere (TOA) reflectance, on the sensor cross-calibration was examined. Results show that absolute radiometric calibration at DNs level was applied to the Landsat-4 and -5 TM (L4 TM and L5 TM) by –1.119% to 0.126%. For L4 TM and L5 TM, the cross-calibration decreased the radiometric measurement level by rescaling at-sensor radiance to DN values. The radiometric changes, –0.77% for L4 TM, 0.95% for L5 TM, –0.26% for L7 ETM+, and –0.01% for L8 OLI, were detected during the cross-calibration stage of converting DNs into TOA reflectance. This study has also indicated that the long-term radiometric performance for the Landsat Collection 1 archive is promising. Supports of these conclusions were demonstrated through the time-series analysis based on the Landsat Collection 1 image stack. Nevertheless, the radiometric changes across the four Landsat sensors raised concerns of the previous Landsat Pre-Collection based results. We suggest that Landsat users should pay attention to differences in results from Pre-Collection and Collection 1 time-series data sets.展开更多
Urban expansion of cities has caused changes in land use and land cover(LULC)in addition to transformations in the spatial characteristics of landscape structure.These alterations have generated heat islands and rise ...Urban expansion of cities has caused changes in land use and land cover(LULC)in addition to transformations in the spatial characteristics of landscape structure.These alterations have generated heat islands and rise of land surface temperature(LST),which consequently have caused a variety of environmental issues and threated the sustainable development of urban areas.Greenbelts are employed as an urban planning containment policy to regulate urban expansion,safeguard natural open spaces,and serve adaptation and mitigation functions.And they are regarded as a powerful measure for enhancing urban environmental sustainability.Despite the fact that,the relation between landscape structure change and variation of LST has been examined thoroughly in many studies,but there is a limitation concerning this relation in semi-arid climate and in greenbelts as well,with the lacking of comprehensive research combing both aspects.Accordingly,this study investigated the spatiotemporal changes of landscape pattern of LULC and their relationship with variation of LST within an inner greenbelt in the semi-arid Erbil City of northern Iraq.The study utilized remote sensing data to retrieve LST,classified LULC,and calculated landscape metrics for analyzing spatial changes during the study period.The results indicated that both composition and configuration of LULC had an impact on the variation of LST in the study area.The Pearson's correlation showed the significant effect of Vegetation 1 type(VH),cultivated land(CU),and bare soil(BS)on LST,as increase of LST was related to the decrease of VH and the increases of CU and BS,while,neither Vegetation 2 type(VL)nor built-up(BU)had any effects.Additionally,the spatial distribution of LULC also exhibited significant effects on LST,as LST was strongly correlated with landscape indices for VH,CU,and BS.However,for BU,only aggregation index metric affected LST,while none of VL metrics had a relation.The study provides insights for landscape planners and policymakers to not only develop more green spaces in greenbelt but also optimize the spatial landscape patterns to reduce the influence of LST on the urban environment,and further promote sustainable development and enhance well-being in the cities with semi-arid climate.展开更多
The frequent occurrence of extreme weather events has rendered numerous landslides to a global natural disaster issue.It is crucial to rapidly and accurately determine the boundaries of landslides for geohazards evalu...The frequent occurrence of extreme weather events has rendered numerous landslides to a global natural disaster issue.It is crucial to rapidly and accurately determine the boundaries of landslides for geohazards evaluation and emergency response.Therefore,the Skip Connection DeepLab neural network(SCDnn),a deep learning model based on 770 optical remote sensing images of landslide,is proposed to improve the accuracy of landslide boundary detection.The SCDnn model is optimized for the over-segmentation issue which occurs in conventional deep learning models when there is a significant degree of similarity between topographical geomorphic features.SCDnn exhibits notable improvements in landslide feature extraction and semantic segmentation by combining an enhanced Atrous Spatial Pyramid Convolutional Block(ASPC)with a coding structure that reduces model complexity.The experimental results demonstrate that SCDnn can identify landslide boundaries in 119 images with MIoU values between 0.8and 0.9;while 52 images with MIoU values exceeding 0.9,which exceeds the identification accuracy of existing techniques.This work can offer a novel technique for the automatic extensive identification of landslide boundaries in remote sensing images in addition to establishing the groundwork for future inve stigations and applications in related domains.展开更多
Land cover is an impression of natural cover on surface of earth such as bare soil, river, grass etc. and utilization of these natural covers for various human needs and purposes by mankind is defined as land use. Lan...Land cover is an impression of natural cover on surface of earth such as bare soil, river, grass etc. and utilization of these natural covers for various human needs and purposes by mankind is defined as land use. Land cover identification, delineation and mapping is important for planning activities, resource management and global monitoring studies while baseline mapping and subsequent monitoring is done by application of land use to get timely information about quantity of land that has been used. The present study has been carried out in Dhund river watershed of Jaipur, Rajasthan which covers an area of about 1828 sq∙km. The minimum and maximum elevation of the area is found to be 214 m and 603 m respectively. Land use and land cover changes of three decades from 1991 to 2021 have been interpreted by using remotes sensing and GIS techniques. ArcGIS software (Arc map 10.2), SOI topographic map, Cartosat-1 DEM and satellite data of Landsat 5 and Landsat 8 have been used for interpretation of eleven classes. The study shows an increase in cultivated land, settlement, waterbody, open forest, plantation and mining due to urbanization because of increasing demands of food, shelter and water while a decrease in dense forest, river, open scrub, wasteland and uncultivated land has also been marked due to destruction of aforementioned by anthropogenic activities such as industrialization resulting in environmental degradation that leads to air, soil and water pollution.展开更多
Due to its abundant rainfall, the city of Libreville, which concentrates more than half of Gabon’s population, is frequently confronted with the impacts of natural disasters such as floods and landslides. This study ...Due to its abundant rainfall, the city of Libreville, which concentrates more than half of Gabon’s population, is frequently confronted with the impacts of natural disasters such as floods and landslides. This study attempts to identify the complex relationships between the dynamics of land use and the role of rainfall in the occurrence of landslides. On the one hand, it uses statistics on landslides compiled from information taken from general news bulletins and, on the other, daily rainfall data obtained from the National Meteorological Department. The study revealed that the Libreville East sector, dominated by Mount Nkol Ogoum, one of Libreville’s most prominent landforms, is affected by a land-use dynamic in which human settlement has been progressing for some thirty years, to the detriment of the original vegetation which, among other things, helped to stabilise the soil on the hillsides and the marshy areas at the foot of the slopes. The result is not only an uncontrolled occupation of the land, but also a major landslide every two years in this part of the city, causing significant loss of life and property. However, an analysis of the time series shows little rainfall variability, marked in particular by a predominance of negative anomalies, and the occurrence of a few exceptional daily rainfall peaks. Similarly, the period from 20 October to 20 November, which receives the most rainfall, also appears to be the most conducive to landslides.展开更多
Soil organic carbon(C)sequestration and nitrogen(N)and phosphorus(P)burial were measured in two floodplain wetlands'soils of the West Fork of the White River watershed(Indiana,United States)whose catchments differ...Soil organic carbon(C)sequestration and nitrogen(N)and phosphorus(P)burial were measured in two floodplain wetlands'soils of the West Fork of the White River watershed(Indiana,United States)whose catchments differed in land use to better understand how land use practices affect wetland C and nutrient retention.The catchment of one floodplain,UpperWest Fork,is dominated by row crop agriculture(61%)whereas the second catchment,Beanblossom Creek,is mostly forested(85%).Soils(0-30cm)of the two floodplain wetlands had similar bulk density(1.23 g/cm^(3)).Soil organic C and N were low in both floodplains but the percent organic C and N was two times greater(3.3%C,0.22%N)in the agricultural floodplain than in the floodplain in the forested catchment(1.5%C,0.14%N).Soil P was three times greater in the agricultural(1100μg/g)than in the forested floodplain(350μg/g).Recent soil accretion based on ^(137)Cs which provides a historical record since 1964(60 years),was two times greater in the agricultural floodplain(2.2mm/year)than in the forested catchment(1.0mm/year).Sediment deposition(2500 g/m^(2)/year),C sequestration(90 g/m^(2)/year),and N burial(7.5g/m^(2)/year)were three times greater in the agricultural floodplain and P burial was seven times greater(3.0 vs.0.41 g/m^(2)/year).Long-term measurements(100 years)based on 210Pb did not show large differences in C sequestration and N burial between the two floodplains though soil accretion and sediment deposition were greater in the forested floodplain.We attribute these higher rates to greater erosion in the watershed before 1950 when the catchment had more agricultural land and before instruction on best management practices to reduce soil erosion.These findings confirm previously published studies that show that P enrichment and accumulation in floodplain soils represent legacy effects of agricultural land use in the catchment.展开更多
This study analyzed four periods of land use raster data in 1992,2002,2012,and 2022,utilizing software tools such as ArcGIS 10.7,Fragstats 4.2,and the PLUS model.The objective was to identify the characteristics of la...This study analyzed four periods of land use raster data in 1992,2002,2012,and 2022,utilizing software tools such as ArcGIS 10.7,Fragstats 4.2,and the PLUS model.The objective was to identify the characteristics of land use changes in the major urban areas of Jingzhou City,specifically in Jingzhou District and Shashi District,over the past 30 years.Additionally,the analysis incorporated 14 influencing factors to determine the primary influencing factors of various land use changes.The findings indicated that:(i)the area designated for construction within the study region had consistently expanded in a distinct north-easterly direction from 1992 to 2022.The primary increase in construction land was attributable to the decrease in cultivated land.Despite a decrease in its proportion,cultivated land remained the predominant landscape throughout this period.(ii)The expansion of construction land led to a reduction in the spatial aggregation of various land types,an increase in fragmentation,a decrease in heterogeneity,and a rise in the complexity of land shapes.(iii)Socio-economic factors,including distances to primary and secondary roads,highways,and natural elements such as precipitation,DEM,and distance to water systems,were the primary driving factors influencing various land use changes.Overall,socio-economic factors serve as the principal driving force of changes in land use landscape patterns in the study area.展开更多
Rural mountain areas in Thailand have a high hazard potential for landslides.Settlements in hazardous areas are expanding and hill slopes are being deforested.Many former forest areas have been converted into agricult...Rural mountain areas in Thailand have a high hazard potential for landslides.Settlements in hazardous areas are expanding and hill slopes are being deforested.Many former forest areas have been converted into agricultural lands,thereby decreasing slope stabilities.Since the beginning of the 21^(st)century disasters caused by landslides have increased in Thailand.The landslides that lead to disasters in villages are in fact debris flows caused by heavy rains and landslides upstream.Landslides resulting from seismic activities are uncommon in Thailand.The landslide hazard risk in Thailand is defined by the hazard(the debris flow,i.e.,landslide prone areas)and the vulnerability(people living in landslide hazard areas).The landslide prone area mapping is based on the geology and the morphology,and the vulnerability upon settlements.The resulting landslide risk map was used to identify all risk areas and consequently the establishment of a community based landslide observation network has been able to reduce the landslide related risks.This network focuses on training local people to understand the risks related to landslides and provides villages with simple tools to detect early signs of threatening landslides and evacuate villagers to safe places.These networks have proven to be very successful,because it was possible to sensibilize and train villagers on the hazard and the risk with the result to effectively protect human lives during several landslide events.展开更多
Many agricultural landscapes have been formed through the interaction and co-evolution of nature and people, and represent the living landscapes shaped over time through intensive and continuous human cultivation. Ter...Many agricultural landscapes have been formed through the interaction and co-evolution of nature and people, and represent the living landscapes shaped over time through intensive and continuous human cultivation. Terraced paddy fields are being re-evaluated to take into account the multiple functions they fill beyond only rice cultivation, particularly their contribution to the national biodiversity strategy of Japan. Since the 1990 s, terraced paddy fields have been considered a representative cultural landscape of Japan and, at the same time, multi-stakeholder conservation activities have been conducted throughout Japan to reverse the increasing abandonment of terraces. Shiroyone Senmaida is an outstanding cultural landscape and a major tourist attraction in Noto Peninsula, Ishikawa Prefecture, which was designated through an initiative by the Food and Agriculture Organization(FAO) as a Globally Important Agricultural Heritage Systems(GIAHS) pilot site in 2011. It is important to clarify tourist preference for terraced paddy field landscapes to contribute to future policy making toward improved agricultural landscape conservation. A key finding of this study is that tourists visiting toenjoy the agricultural landscape are also concerned on the sustainability of the farming methods and preferred to maintain the naturalness of the landscape. Respondents with higher educational levels and greater concern for the biological and traditional farming knowledge aspects of the rice terraces were also more inclined to favor sustainable farming practices. Tourists preferred to maintain the naturalness and rurality of the agricultural landscape, and indicated that construction of excessive tourist facilities would cause the landscape to deteriorate. It was suggested that the local community and surroundings, including rural settlements, hills, and forests, should also be conserved together with the scenic terrace.展开更多
Weihe River basin is of great significance to analyze the changes of land use pattern and landscape ecological risk and to improve the ecological basis of regional development.Based on land use data of the Weihe River...Weihe River basin is of great significance to analyze the changes of land use pattern and landscape ecological risk and to improve the ecological basis of regional development.Based on land use data of the Weihe River basin in 2000,2010,and 2020,with the support of Aeronautical Reconnaissance Coverage Geographic Information System(ArcGIS),GeoDa,and other technologies,this study analyzed the spatial-temporal characteristics and driving factors of land use pattern and landscape ecological risk.Results showed that land use structure of the Weihe River basin has changed significantly,with the decrease of cropland and the increase of forest land and construction land.In the past 20 a,cropland has decreased by 7347.70 km2,and cropland was mainly converted into forest land,grassland,and construction land.The fragmentation and dispersion of ecological landscape pattern in the Weihe River basin were improved,and land use pattern became more concentrated.Meanwhile,landscape ecological risk of the Weihe River basin has been improved.Severe landscape ecological risk area decreased by 19,177.87 km2,high landscape ecological risk area decreased by 3904.35 km2,and moderate and low landscape ecological risk areas continued to increase.It is worth noting that landscape ecological risks in the upper reaches of the Weihe River basin are still relatively serious,especially in the contiguous areas of high ecological risk,such as Tianshui,Pingliang,Dingxi areas and some areas of Ningxia Hui Autonomous Region.Landscape ecological risk showed obvious spatial dependence,and high ecological risk area was concentrated.Among the driving factors,population density,precipitation,normalized difference vegetation index(NDVI),and their interactions are the most important factors affecting the landscape ecological risk of the Weihe River basin.The findings significantly contribute to our understanding of the ecological dynamics in the Weihe River basin,providing crucial insights for sustainable management in the region.展开更多
Landscape ecology and landscape pattern analysis are important components of national-scale programs to identify trends in land cover change because: 1) Statistics on changes in land cover prop...Landscape ecology and landscape pattern analysis are important components of national-scale programs to identify trends in land cover change because: 1) Statistics on changes in land cover proportions are not spatial. A change matrix derived from GIS provides useful information, but it does not show the spatial form of change in the landscape. Landscape pattern metrics reveal spatial pattern. 2) A growing body of literature has shown that a change in landscape pattern might indicate important changes in ecological functions: forest connectivity and species movements, number and size of farm patches, effects on water quality. Spatial pattern is important in structuring ecological communities and in maintaining existence of competitors. Spatial pattern may be determined by disturbance and may in turn, determine how disturbances propagate through the system. 3) Sometimes landscape pattern may not significantly change, even though land cover proportions do change. Or, vice-versa, sometimes landscape pattern can significantly change, even though land cover proportions don't significantly change. 4) Landscape pattern is an inherent and important part of describing landscapes: based on the literature, one of the most important descriptive characteristics of a landscape is its texture. The objectives of this paper are to: 1) Explain the importance of the role of landscape ecology and landscape pattern analysis in land cover change studies; 2) Review the literature that specifically incorporates landscape ecology into land cover change studies; and 3) List the theoretical and technical issues involved and suggest solutions for them.展开更多
基金Under the auspices of Zhejiang Provincial Natural Science Foundation of China(No.LY19C160007)。
文摘In recent years,rapid urbanization has had a profound impact on landscape stability.As a typical example of China's rapid urbanization,Hangzhou has also experienced significant landscape changes,which have profoundly affected its ecological stability.Taking Hangzhou as an example,this study integrates land use change data from 1980 to 2020,combines dynamic simulation and ecological modeling techniques,and carries out a comprehensive analysis of historical trends and future predictions,to provide valuable insights into the complex interactions between urban expansion and landscape stability.The results indicate that:1)between 1980 and2020,Hangzhou experienced a significant increase in construction land at the expense of arable land,leading to a gradual decline in landscape stability,though the downward trend has slowed in recent years.2)The spatial distribution of landscape stability shows clear aggregation patterns,with lower stability concentrated in economically active flatlands and higher stability in the mountainous western regions.3)By 2040,further urban expansion is predicted to occur alongside increased landscape integration,reflecting the positive effects of ecological protection strategies.This study highlights the universal challenges of balancing economic growth with ecological stability in rapidly urbanizing regions.The combination of advanced simulation models and spatiotemporal analysis demonstrates a replicable framework for assessing urban expansion's ecological impacts.These findings underscore the importance of tailoring urban planning and ecological policies to address regional disparities,providing valuable insights for sustainable urban development and landscape management globally.
基金supported by the National Key R&D Program of China(Grant No.2024YFC3012702)National Natural Science Foundation of China(Grant No.42371014)+2 种基金Hubei Provincial Engineering Research Center of Slope Habitat Construction Technique Using Cement-based Materials Open Research Program(Grant No.2022SNJ11)National Natural Science Foundation of China(Grant No.42201094)Hubei Key Laboratory of Disaster Prevention and Mitigation(China Three Gorges University)Open Research Program(Grant No.2022KJZ12)。
文摘The relationship between landslides,land use,and sediment connectivity is not only a critical interdisciplinary topic,but also remains a challenging issue in assessing dynamic landslide susceptibility within reservoir areas.To explore the interactions among landslide,land use changes,and sediment dynamic,this study took Zigui Basin,the head area of the Three Gorges Reservoir,as the study area to examine this triadic relationship by single-factor detection and interactive detection.Here,we utilized Dynamic Attitude(DA)analysis to quantify land use changes and applied the Index of Connectivity(IC)to assess sediment connectivity evolution from 2018 to 2023.A multi-temporal analysis using the Landslide Susceptibility Index(LSI)was conducted to evaluate the degree of transformation in the three objects and the influence of these changes on the landslide susceptibility.According to the spatial analyst and statistics tools in ArcGIS,the results reveal that most of the landslides distributed in areas with high land use dynamic attitude,such as cultivated land transfers to forestland or garden plot,and the garden plot continuously increased across the study period with largest variation of 5%and an increment of 1.9%.Furthermore,linkage between land use and sediment transport can be effectively quantified by IC,and the resulting map indicated that garden plot increased,and catchment channel characteristics had a greater influence on the IC value than differences in vegetation cover.A comprehensive evaluation of the differences among the susceptibility maps reveals that the very high susceptibility classes are predominantly influenced by enhanced connectivity,whereas land use change has a greater effect on medium-low susceptibility region than that of sediment evolution.That is,both changes of land use and connectivity have positively correlated with landslide activity,but they exhibit differential influences on landslides susceptibility.
基金supported by the National Social Science Foundation of China(Grant No.20CMZ033)Fundamental Research Funds for the Central Universities(CCNU24ZZ125).
文摘Mountainous minority regions in China,characterized by abundant natural and cultural resources,ecologically fragile environments,and often geographically remote locations,pose distinct developmental challenges and opportunities.Despite the complexity and typicality of Chinese mountainous ethnic minority regions in terms of eco-cultural tourism and land use dynamics,the interplay among tourism development,land use changes,and landscape ecological risk in these specific contexts has received insufficient attention.To explore how eco-cultural tourism development in ethnic minority mountainous regions affects land use and landscape ecology,this study investigates the evolution of land use in Southeast Guizhou Province from 1980-2020,integrating GIS spatial analysis,the landscape pattern index and landscape ecological risk index analysis.Over the past four decades(1980-2020),eco-cultural tourism has driven significant land use transformations characterized by substantial expansion of building land,growth of ecological land(notably forest land and water areas),and reduction of cultivated land.Concurrently,landscape ecological risk evolved through distinct phases-showing an overall increase during 1980-2000 with expanding medium-risk zones,followed by stabilization from 2000-2020.Tourism development accelerated these land transitions while fostering multifunctional compound land uses,enhancing both land value and utilization efficiency.Crucially,eco-cultural tourism in ethnic regions demonstrates capacity to reconcile ecological conservation with economic development,providing transferable models for similar regions globally.
基金funded by the National Natural Science Foundation of China(Grant No.42271116)。
文摘As one of the important wintering areas along the East Asian-Australasian Flyway,wetlands in the Yangtze River floodplain face threats from land-use changes,yet its effects on wintering waterbirds at the landscape level remain understudied,impeding conservation practice.Here,using survey data collected across 14 inland lakes in Jiangsu Province in 2022,we calculated wintering waterbirds diversity(taxonomic,functional,phylogenetic)and assembly patterns(MPD/MNTD of functional and phylogenetic).Then,we interpreted satellite imagery of lake areas and buffer zones(5 km),and partitioned them into three land-use and landscape index categories(anthropogenic,ecological,and lake landscape).Finally,we employed multiple linear regression and hierarchical partitioning to explain the influence of landscape scales on wintering waterbird communities.Our results showed that the diversity and assembly of regional wintering waterbird communities tended to be consistent across taxonomic,functional,and phylogenetic dimensions.The standardized diversity indices indicated that functional assembly of communities tends to be clustered at both local and regional scale.In contrast,the phylogenetic structure showed a predominantly overdispersed pattern in most lakes at the local scale,while neutral processes dominated at the regional scale.Modeling showed that selected variables explained waterbird diversity and assembly well.Lake fragmentation increased species evenness but reduced other diversity indices,while landscape evenness was negatively associated with functional and phylogenetic assembly.Among anthropogenic factors,aquaculture ponds and impervious surfaces reduced all diversity dimensions,whereas cropland connectivity enhanced phylogenetic diversity.These factors had consistent effects on community assembly.For ecological variables,grassland area enhanced functional and phylogenetic diversity but led to more clustered functional assembly.Overall,maintaining the integrity and connectivity of lakes and their surrounding landscapes is essential for sustaining waterbird diversity and guiding wetland restoration.
基金supported by the National Natural Science Foundation of China(42377458 and 41907411).
文摘The Leymus chinensis grassland is one of themost widely distributed associations in the warmtemperate grassland and due to overgrazing in recent years,it has experienced varying degrees of degradation.Vegetative regeneration via bud banks serves as the primaryway of vegetation reproduction in the L.chinensis grassland ecosystem.However,the role of the bud bank in the vegetation regeneration of grazing grassland remains unclear.Based on the relationship between the under-ground bud bank and above-ground vegetation of L.chinensis grassland under different grazing stages,this study aimed to explore whether the grazing grassland could self-recover through the existing bud bank.The findings revealed that the bud density initially increased and then decreased with increasing grazing intensity,indicating that appropriate grazing promoted vegetation renewal.Moreover,grazing significantly influenced the composition of the bud bank:during the early grazing stage,the rhizome buds accounted for the main part,and tiller buds dominated during the mid-stage grazing;while during the late-stage grazing,root-sprouting buds prevailed.The meristem restriction index for light,moderate,and heavy grazing grasslands was close to one;conversely,overgrazing and extreme overgrazing grasslands exhibited the highermeristemrestriction index(2.00,3.19),suggesting that plant regeneration was constrained by bud banks under light-grazing conditions where regenerate rates failed to meet above-ground modular’s recovery requirements following overgrazing and extreme overgrazing events.Consequently,moderate grazing grasslands could achieve natural community recovery by continuously adjusting their vegetative regeneration strategies.Understanding the role of bud banks in vegetative regeneration in grazing grassland will not only supply theoretical support for the ecological succession process of degraded grassland but also provide practical experience for the sustainable management of the L.chinensis grassland ecosystem.
基金supported by the project China Postdoctoral Science Foundation under Grant No.2024M760408the project Research on Artificial Recruitment,Rescue and Breeding of Scaly-sided Merganser from Jilin Forestry and Grassland Bureau and the Fundamental Research Funds for the Central Universities,China (2412024QD021)。
文摘The process of agricultural intensification has led to significant reductions in biodiversity globally.Previous studies examined the role of semi-natural habitats within agroecosystems in supporting bird communities,but few have considered the effects of landscape agricultural intensity on avian conservation potential of seminatural habitats.Here,we disentangle the relative effects of semi-natural habitats within different landscape agricultural intensities on bird community composition in central and eastern Jilin Province,China.We established 322 sampling sites distributed across low,middle,and high landscape agricultural intensities,with 103,118,and 101 sites respectively.Each sampling site was visited two times in May and June 2023 to test the dissimilarities in bird composition between different landscape agricultural intensities.We found that middleintensity agriculture supported the highest bird diversity in most cases,but low-intensity plays an important role in maintaining insectivorous birds.We used generalized linear models and model selection to assess the relative impacts of semi-natural habitats on bird community along agricultural intensity respectively.Our results showed that the effects of agriculture on bird communities were predominantly influenced by the amount of semi-natural habitats,with effects that differ in accordance with the level of landscape agricultural intensity.Priority should be given to preserve or/and plant these semi-natural habitats in middle-intensity agriculture due to the stronger effect sizes on bird diversity.Specifically,we suggested preserving and promoting woodlands and shrubs in high-intensity agriculture,and simultaneously increasing crop diversity to protect bird diversity in agriculture landscapes in the context of increasing crop intensification globally.
文摘Agricultural management practices influence soil health.In this study,agricultural lands of cold arid Hanna village,Balochistan,Pakistan,were studied to assess soil properties and the abundance of soil macrofauna species.Five orchards,five tree-based intercropping(TBI)systems,two croplands and a barren unprotected rangeland were sampled.Soil properties,such as texture,concentrations of organic matter(SOM),organic carbon(SOC),mineral nitrogen and bioavailable phosphorus,pH and electrical conductivity were analyzed.The abundance and species of soil surface-dwelling and upper soil layer-dwelling(0-5 cm)macrofauna were also measured.Orchards and croplands were older than TBI systems.than the same agricultural systems(cropland or orchards),which were under intense tillage practice or receiving no fertilizer input.Our results demonstrate that the diversified cropping systems with the reduced(shallow)tillage and the amendment of both synthetic and organic fertilizers,promoted soil quality in this cold-winter desert.This study is a source of evidence for the farmers of this region,which highlights the importance of conservation agriculture and crop diversification under TBI system for improving soil quality.It warrants further investigation to evaluate biological indicators of soil health(soil microbial biomass,microbial diversity,microfauna,mesofauna and macrofauna)being influenced by various management practices in this region.Furthermore,the relationship between soil quality and crop production under various management practices in this region needs to be evaluated.Such an extensive study will further help encourage farmers to adopt the best management practice in their fields.
基金funded by Taif University,Saudi Arabia,Project No.(TU-DSPP-2025-30)The Science and Technology Fellowship Trust(SL No.39.00.0000.035.22.013.19.144)under the Ministry of Science and Technology of Bangladesh partially financed the current research。
文摘Improving crop productivity and soil fertility through the balanced application of inorganic and organic nutrient sources is a sustainable approach in modern agriculture.Char land soils,widely distributed in riverine Bangladesh,are generally low in organic matter status and deficient in necessary nutrient elements for crop production.Addressing this challenge,the present study was conducted to investigate the effects of various organic nutrient sources with inorganic fertilizers on crop yields,nutrient uptake,and soil fertility in farm(L1)and char land(L2)of Brahmaputra River in Mymensingh,Bangladesh from 2022(Y1)to 2023(Y2).For each location,eight treatments viz.T1(Control),T2[100%recommended fertilizer dose(RFD)],T3(75%RFD),T4(75%N from RFD 25%N from cow dung),T5(75%+N from RFD 25%N from poultry manure),T6(75%N from RFD 25%N from vermicompost),T7(75%N from++RFD 25%N from household compost)and T8(75%N from RFD 25%N from rice straw compost)were arranged in++a randomized complete block design with three replications using Wheat–Mungbean–T.Aman rice cropping pattern where three way interaction was considered for results.Treatment T5 performed the best in both years in both locations as it enhanced the yield components(p 0.05)and caused yield increment over control.The yield improvement in<Char land soils was higher than that in farm soils.For all three crops,treatment T5 consistently augmented the uptake of nitrogen,phosphorus,potassium,and sulphur by different parts of the crops and improved soil fertility properties such as organic matter status,cation exchange capacity,total nitrogen,available phosphorus,and sulphur as well as exchangeable potassium in both locations in both years.Cost and return analysis of different treatments for the whole cropping system showed that the highest marginal benefit-cost ratio(16.35 and 15.07)and gross return(about Tk 768,595/ha and 728,341/ha)were obtained from the T5 treatment in farm soils and Char land soils,respectively.Followed by poultry manure,vermicompost performed well in addition to mineral fertilizers for improving crop yield and soil fertility but its economic efficiency was less due to high input cost.These findings may be useful to the smallholder farmers in char areas,who could benefit from increased productivity,reduced reliance on chemical fertilizers,and improved soil health,contributing to the long-term sustainability of char land agriculture.
文摘Rainfall-induced landslides,exacerbated by climate change,require urgent attention to identify vulnerable regions and propose effective risk mitigation measures.Extensive research underscores the significant impact of vegetation on soil properties and slope stability,emphasizing the necessity to incorporate vegetation effects into regional landslide susceptibility mapping.This review thoroughly examines research integrating vegetation into landslide susceptibility mapping,encompassing qualitative,semi-quantitative,and quantitative forecasting methods.It highlights the importance of incorporating vegetation aspects into these methods for comprehensive and accurate landslide susceptibility assessment.This review explores the diverse roles of vegetation in slope stability,covering both aggregated impacts and individual influences,including mechanical and hydrological effects on soil properties,as well as the implications of evapotranspiration and rainwater interception on slope stability.While aggregated roles are integrated into non-deterministic methods as input layers,individual roles are considered in deterministic methods.In the application of deterministic methods,it is noteworthy that a considerable number of studies primarily concentrate on the mechanical impact,particularly the reinforcement provided by root cohesion.The review also explores limitations and highlights future research prospects.In the context of mapping landslide susceptibility amid changing climatic conditions,data-driven techniques encounter challenges,while deterministic methods present their advantages.Stressing the significance of hydrological impacts,the paper recommends incorporating vegetation influences on unsaturated soil properties,including the soil water characteristic curve and soil permeability,along with pre-wetting suction due to evapotranspiration and potential rainwater interception.
文摘This study evaluates the long-term radiometric performance of the USGS new released Landsat Collection 1 archive, including the absolute calibration of each Landsat sensor as well as the relative cross-calibration among the four most popular Landsat sensors. A total of 920 Landsat Collection 1 scenes were evaluated against the corresponding Pre-Collection images over a Pseudo-Invariant Site, Railroad Valley Playa Nevada, United States (RVPN). The radiometric performance of the six Landsat solar reflective bands, in terms of both Digital Numbers (DNs) and at-sensor Top of Atmosphere (TOA) reflectance, on the sensor cross-calibration was examined. Results show that absolute radiometric calibration at DNs level was applied to the Landsat-4 and -5 TM (L4 TM and L5 TM) by –1.119% to 0.126%. For L4 TM and L5 TM, the cross-calibration decreased the radiometric measurement level by rescaling at-sensor radiance to DN values. The radiometric changes, –0.77% for L4 TM, 0.95% for L5 TM, –0.26% for L7 ETM+, and –0.01% for L8 OLI, were detected during the cross-calibration stage of converting DNs into TOA reflectance. This study has also indicated that the long-term radiometric performance for the Landsat Collection 1 archive is promising. Supports of these conclusions were demonstrated through the time-series analysis based on the Landsat Collection 1 image stack. Nevertheless, the radiometric changes across the four Landsat sensors raised concerns of the previous Landsat Pre-Collection based results. We suggest that Landsat users should pay attention to differences in results from Pre-Collection and Collection 1 time-series data sets.
文摘Urban expansion of cities has caused changes in land use and land cover(LULC)in addition to transformations in the spatial characteristics of landscape structure.These alterations have generated heat islands and rise of land surface temperature(LST),which consequently have caused a variety of environmental issues and threated the sustainable development of urban areas.Greenbelts are employed as an urban planning containment policy to regulate urban expansion,safeguard natural open spaces,and serve adaptation and mitigation functions.And they are regarded as a powerful measure for enhancing urban environmental sustainability.Despite the fact that,the relation between landscape structure change and variation of LST has been examined thoroughly in many studies,but there is a limitation concerning this relation in semi-arid climate and in greenbelts as well,with the lacking of comprehensive research combing both aspects.Accordingly,this study investigated the spatiotemporal changes of landscape pattern of LULC and their relationship with variation of LST within an inner greenbelt in the semi-arid Erbil City of northern Iraq.The study utilized remote sensing data to retrieve LST,classified LULC,and calculated landscape metrics for analyzing spatial changes during the study period.The results indicated that both composition and configuration of LULC had an impact on the variation of LST in the study area.The Pearson's correlation showed the significant effect of Vegetation 1 type(VH),cultivated land(CU),and bare soil(BS)on LST,as increase of LST was related to the decrease of VH and the increases of CU and BS,while,neither Vegetation 2 type(VL)nor built-up(BU)had any effects.Additionally,the spatial distribution of LULC also exhibited significant effects on LST,as LST was strongly correlated with landscape indices for VH,CU,and BS.However,for BU,only aggregation index metric affected LST,while none of VL metrics had a relation.The study provides insights for landscape planners and policymakers to not only develop more green spaces in greenbelt but also optimize the spatial landscape patterns to reduce the influence of LST on the urban environment,and further promote sustainable development and enhance well-being in the cities with semi-arid climate.
基金supported by the National Natural Science Foundation of China(Grant Nos.42090054,41931295)the Natural Science Foundation of Hubei Province of China(2022CFA002)。
文摘The frequent occurrence of extreme weather events has rendered numerous landslides to a global natural disaster issue.It is crucial to rapidly and accurately determine the boundaries of landslides for geohazards evaluation and emergency response.Therefore,the Skip Connection DeepLab neural network(SCDnn),a deep learning model based on 770 optical remote sensing images of landslide,is proposed to improve the accuracy of landslide boundary detection.The SCDnn model is optimized for the over-segmentation issue which occurs in conventional deep learning models when there is a significant degree of similarity between topographical geomorphic features.SCDnn exhibits notable improvements in landslide feature extraction and semantic segmentation by combining an enhanced Atrous Spatial Pyramid Convolutional Block(ASPC)with a coding structure that reduces model complexity.The experimental results demonstrate that SCDnn can identify landslide boundaries in 119 images with MIoU values between 0.8and 0.9;while 52 images with MIoU values exceeding 0.9,which exceeds the identification accuracy of existing techniques.This work can offer a novel technique for the automatic extensive identification of landslide boundaries in remote sensing images in addition to establishing the groundwork for future inve stigations and applications in related domains.
文摘Land cover is an impression of natural cover on surface of earth such as bare soil, river, grass etc. and utilization of these natural covers for various human needs and purposes by mankind is defined as land use. Land cover identification, delineation and mapping is important for planning activities, resource management and global monitoring studies while baseline mapping and subsequent monitoring is done by application of land use to get timely information about quantity of land that has been used. The present study has been carried out in Dhund river watershed of Jaipur, Rajasthan which covers an area of about 1828 sq∙km. The minimum and maximum elevation of the area is found to be 214 m and 603 m respectively. Land use and land cover changes of three decades from 1991 to 2021 have been interpreted by using remotes sensing and GIS techniques. ArcGIS software (Arc map 10.2), SOI topographic map, Cartosat-1 DEM and satellite data of Landsat 5 and Landsat 8 have been used for interpretation of eleven classes. The study shows an increase in cultivated land, settlement, waterbody, open forest, plantation and mining due to urbanization because of increasing demands of food, shelter and water while a decrease in dense forest, river, open scrub, wasteland and uncultivated land has also been marked due to destruction of aforementioned by anthropogenic activities such as industrialization resulting in environmental degradation that leads to air, soil and water pollution.
文摘Due to its abundant rainfall, the city of Libreville, which concentrates more than half of Gabon’s population, is frequently confronted with the impacts of natural disasters such as floods and landslides. This study attempts to identify the complex relationships between the dynamics of land use and the role of rainfall in the occurrence of landslides. On the one hand, it uses statistics on landslides compiled from information taken from general news bulletins and, on the other, daily rainfall data obtained from the National Meteorological Department. The study revealed that the Libreville East sector, dominated by Mount Nkol Ogoum, one of Libreville’s most prominent landforms, is affected by a land-use dynamic in which human settlement has been progressing for some thirty years, to the detriment of the original vegetation which, among other things, helped to stabilise the soil on the hillsides and the marshy areas at the foot of the slopes. The result is not only an uncontrolled occupation of the land, but also a major landslide every two years in this part of the city, causing significant loss of life and property. However, an analysis of the time series shows little rainfall variability, marked in particular by a predominance of negative anomalies, and the occurrence of a few exceptional daily rainfall peaks. Similarly, the period from 20 October to 20 November, which receives the most rainfall, also appears to be the most conducive to landslides.
文摘Soil organic carbon(C)sequestration and nitrogen(N)and phosphorus(P)burial were measured in two floodplain wetlands'soils of the West Fork of the White River watershed(Indiana,United States)whose catchments differed in land use to better understand how land use practices affect wetland C and nutrient retention.The catchment of one floodplain,UpperWest Fork,is dominated by row crop agriculture(61%)whereas the second catchment,Beanblossom Creek,is mostly forested(85%).Soils(0-30cm)of the two floodplain wetlands had similar bulk density(1.23 g/cm^(3)).Soil organic C and N were low in both floodplains but the percent organic C and N was two times greater(3.3%C,0.22%N)in the agricultural floodplain than in the floodplain in the forested catchment(1.5%C,0.14%N).Soil P was three times greater in the agricultural(1100μg/g)than in the forested floodplain(350μg/g).Recent soil accretion based on ^(137)Cs which provides a historical record since 1964(60 years),was two times greater in the agricultural floodplain(2.2mm/year)than in the forested catchment(1.0mm/year).Sediment deposition(2500 g/m^(2)/year),C sequestration(90 g/m^(2)/year),and N burial(7.5g/m^(2)/year)were three times greater in the agricultural floodplain and P burial was seven times greater(3.0 vs.0.41 g/m^(2)/year).Long-term measurements(100 years)based on 210Pb did not show large differences in C sequestration and N burial between the two floodplains though soil accretion and sediment deposition were greater in the forested floodplain.We attribute these higher rates to greater erosion in the watershed before 1950 when the catchment had more agricultural land and before instruction on best management practices to reduce soil erosion.These findings confirm previously published studies that show that P enrichment and accumulation in floodplain soils represent legacy effects of agricultural land use in the catchment.
文摘This study analyzed four periods of land use raster data in 1992,2002,2012,and 2022,utilizing software tools such as ArcGIS 10.7,Fragstats 4.2,and the PLUS model.The objective was to identify the characteristics of land use changes in the major urban areas of Jingzhou City,specifically in Jingzhou District and Shashi District,over the past 30 years.Additionally,the analysis incorporated 14 influencing factors to determine the primary influencing factors of various land use changes.The findings indicated that:(i)the area designated for construction within the study region had consistently expanded in a distinct north-easterly direction from 1992 to 2022.The primary increase in construction land was attributable to the decrease in cultivated land.Despite a decrease in its proportion,cultivated land remained the predominant landscape throughout this period.(ii)The expansion of construction land led to a reduction in the spatial aggregation of various land types,an increase in fragmentation,a decrease in heterogeneity,and a rise in the complexity of land shapes.(iii)Socio-economic factors,including distances to primary and secondary roads,highways,and natural elements such as precipitation,DEM,and distance to water systems,were the primary driving factors influencing various land use changes.Overall,socio-economic factors serve as the principal driving force of changes in land use landscape patterns in the study area.
文摘Rural mountain areas in Thailand have a high hazard potential for landslides.Settlements in hazardous areas are expanding and hill slopes are being deforested.Many former forest areas have been converted into agricultural lands,thereby decreasing slope stabilities.Since the beginning of the 21^(st)century disasters caused by landslides have increased in Thailand.The landslides that lead to disasters in villages are in fact debris flows caused by heavy rains and landslides upstream.Landslides resulting from seismic activities are uncommon in Thailand.The landslide hazard risk in Thailand is defined by the hazard(the debris flow,i.e.,landslide prone areas)and the vulnerability(people living in landslide hazard areas).The landslide prone area mapping is based on the geology and the morphology,and the vulnerability upon settlements.The resulting landslide risk map was used to identify all risk areas and consequently the establishment of a community based landslide observation network has been able to reduce the landslide related risks.This network focuses on training local people to understand the risks related to landslides and provides villages with simple tools to detect early signs of threatening landslides and evacuate villagers to safe places.These networks have proven to be very successful,because it was possible to sensibilize and train villagers on the hazard and the risk with the result to effectively protect human lives during several landslide events.
文摘Many agricultural landscapes have been formed through the interaction and co-evolution of nature and people, and represent the living landscapes shaped over time through intensive and continuous human cultivation. Terraced paddy fields are being re-evaluated to take into account the multiple functions they fill beyond only rice cultivation, particularly their contribution to the national biodiversity strategy of Japan. Since the 1990 s, terraced paddy fields have been considered a representative cultural landscape of Japan and, at the same time, multi-stakeholder conservation activities have been conducted throughout Japan to reverse the increasing abandonment of terraces. Shiroyone Senmaida is an outstanding cultural landscape and a major tourist attraction in Noto Peninsula, Ishikawa Prefecture, which was designated through an initiative by the Food and Agriculture Organization(FAO) as a Globally Important Agricultural Heritage Systems(GIAHS) pilot site in 2011. It is important to clarify tourist preference for terraced paddy field landscapes to contribute to future policy making toward improved agricultural landscape conservation. A key finding of this study is that tourists visiting toenjoy the agricultural landscape are also concerned on the sustainability of the farming methods and preferred to maintain the naturalness of the landscape. Respondents with higher educational levels and greater concern for the biological and traditional farming knowledge aspects of the rice terraces were also more inclined to favor sustainable farming practices. Tourists preferred to maintain the naturalness and rurality of the agricultural landscape, and indicated that construction of excessive tourist facilities would cause the landscape to deteriorate. It was suggested that the local community and surroundings, including rural settlements, hills, and forests, should also be conserved together with the scenic terrace.
基金the National Natural Science Foundation of China(31971859)the Doctoral Research Start-up Fund of Northwest A&F University,China(Z1090121109)the Shaanxi Science and Technology Development Plan Project(2023-JC-QN-0197).
文摘Weihe River basin is of great significance to analyze the changes of land use pattern and landscape ecological risk and to improve the ecological basis of regional development.Based on land use data of the Weihe River basin in 2000,2010,and 2020,with the support of Aeronautical Reconnaissance Coverage Geographic Information System(ArcGIS),GeoDa,and other technologies,this study analyzed the spatial-temporal characteristics and driving factors of land use pattern and landscape ecological risk.Results showed that land use structure of the Weihe River basin has changed significantly,with the decrease of cropland and the increase of forest land and construction land.In the past 20 a,cropland has decreased by 7347.70 km2,and cropland was mainly converted into forest land,grassland,and construction land.The fragmentation and dispersion of ecological landscape pattern in the Weihe River basin were improved,and land use pattern became more concentrated.Meanwhile,landscape ecological risk of the Weihe River basin has been improved.Severe landscape ecological risk area decreased by 19,177.87 km2,high landscape ecological risk area decreased by 3904.35 km2,and moderate and low landscape ecological risk areas continued to increase.It is worth noting that landscape ecological risks in the upper reaches of the Weihe River basin are still relatively serious,especially in the contiguous areas of high ecological risk,such as Tianshui,Pingliang,Dingxi areas and some areas of Ningxia Hui Autonomous Region.Landscape ecological risk showed obvious spatial dependence,and high ecological risk area was concentrated.Among the driving factors,population density,precipitation,normalized difference vegetation index(NDVI),and their interactions are the most important factors affecting the landscape ecological risk of the Weihe River basin.The findings significantly contribute to our understanding of the ecological dynamics in the Weihe River basin,providing crucial insights for sustainable management in the region.
基金USGS Geographic Research and Applications Programthe U.S. Environmental Protection Agency Landscape Ecology Program in Las Vegas (Interagency Agreement DW14938108-01-0)and the NASA Land Cover/Land Use Change Program
文摘Landscape ecology and landscape pattern analysis are important components of national-scale programs to identify trends in land cover change because: 1) Statistics on changes in land cover proportions are not spatial. A change matrix derived from GIS provides useful information, but it does not show the spatial form of change in the landscape. Landscape pattern metrics reveal spatial pattern. 2) A growing body of literature has shown that a change in landscape pattern might indicate important changes in ecological functions: forest connectivity and species movements, number and size of farm patches, effects on water quality. Spatial pattern is important in structuring ecological communities and in maintaining existence of competitors. Spatial pattern may be determined by disturbance and may in turn, determine how disturbances propagate through the system. 3) Sometimes landscape pattern may not significantly change, even though land cover proportions do change. Or, vice-versa, sometimes landscape pattern can significantly change, even though land cover proportions don't significantly change. 4) Landscape pattern is an inherent and important part of describing landscapes: based on the literature, one of the most important descriptive characteristics of a landscape is its texture. The objectives of this paper are to: 1) Explain the importance of the role of landscape ecology and landscape pattern analysis in land cover change studies; 2) Review the literature that specifically incorporates landscape ecology into land cover change studies; and 3) List the theoretical and technical issues involved and suggest solutions for them.
